[0/8] usb: gadget: uvc: Improve configfs support

Message

Laurent Pinchart Aug. 1, 2018, 12:29 a.m. UTC

Hello,

This patch series reworks the UVC gadget function configfs implementation to
support multiple UVC functions in a single device and 

The first two patches simplify the code (01/08) and improve readability
(02/08).

The series then moves to dynamically allocating all configfs groups (03/08) to
support multiple instances. As a consequence we have to expose the interface
numbers through new configfs attributes (04/08) in order to let the userspace
helper application discover them.

The next three patches add and document new bFormatIndex (05/08 and 06/08) and
bFrameIndex (07/08) configfs attributes to expose indices of UVC format and
frame descriptors to userspace, allowing their dynamic discovery.

The last patch finally fixes a bug that allowed modification of descriptors
after linking them (08/08).

Felipe, all this is based on top of your testing/next branch, and is a
candidate for v4.20. Please let me know if I should base the patches on a
different branch.

Joel Pepper (2):
  usb: gadget: uvc: configfs: Add bFrameIndex attributes
  usb: gadget: uvc: configfs: Prevent format changes after linking
    header

Laurent Pinchart (6):
  usb: gadget: uvc: configfs: Don't wrap groups unnecessarily
  usb: gadget: uvc: configfs: Add section header comments
  usb: gadget: uvc: configfs: Allocate groups dynamically
  usb: gadget: uvc: configfs: Add interface number attributes
  usb: gadget: uvc: configfs: Add bFormatIndex attributes
  usb: gadget: uvc: configfs: Document the bFormatIndex attribute

 Documentation/ABI/testing/configfs-usb-gadget-uvc |  16 +
 drivers/usb/gadget/function/f_uvc.c               |  10 +-
 drivers/usb/gadget/function/u_uvc.h               |   3 +
 drivers/usb/gadget/function/uvc_configfs.c        | 821 +++++++++++++---------
 4 files changed, 532 insertions(+), 318 deletions(-)